Back-to-back solid state lighting devices and associated methods

ABSTRACT

Solid state lights (SSLs) including a back-to-back solid state emitters (SSEs) and associated methods are disclosed herein. In various embodiments, an SSL can include a carrier substrate having a first surface and a second surface different from the first surface. First and second through substrate interconnects (TSIs) can extend from the first surface of the carrier substrate to the second surface. The SSL can further include a first and a second SSE, each having a front side and a back side opposite the front side. The back side of the first SSE faces the first surface of the carrier substrate and the first SSE is electrically coupled to the first and second TSIs. The back side of the second SSE faces the second surface of the carrier substrate and the second SSE is electrically coupled to the first and second TSIs.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.15/252,156, filed Aug. 30, 2016, now U.S. Pat. No. 10,062,677, which isa divisional of U.S. application Ser. No. 12/874,396, filed Sep. 2,2010, now U.S. Pat. No. 9,443,834, each of which is incorporated hereinby reference in its entirety.

TECHNICAL FIELD

The present technology is related to solid state lights (“SSLs”) andassociated methods of operation and manufacture. In particular, thepresent disclosure is related to SSLs having at least two solid stateemitters (“SSEs”) oriented in a back-to-back configuration andassociated methods of packaging.

BACKGROUND

Solid state lights (“SSLs”) use solid state emitters (“SSEs”) as sourcesof illumination. Generally, SSLs generate less heat, provide greaterresistance to shock and vibration, and have longer life spans thanconventional lighting devices that use filaments, plasma, or gas assources of illumination (e.g., florescent or incandescent lights).

A conventional type of SSL is a “white light” SSE. White light requiresa mixture of wavelengths to be perceived as white by human eyes.However, SSEs typically only emit light at one particular wavelength(e.g., blue light), so SSEs must be modified to generate white light.One conventional technique for modulating the light from SSEs includesdepositing a converter material (e.g., phosphor) on the SSE. Forexample, FIG. 1A shows a conventional SSL 10 that includes a support 2,an SSE 4 attached to the support 2, and a converter material 6 on theSSE 4. The SSE 4 typically emits blue light that stimulates theconverter material 6 to emit light at a desired frequency (e.g., yellowlight). The combination of the emissions from the SSE 4 and theconverter material 6 appears white to human eyes if the wavelengths ofthe emissions are matched appropriately.

FIG. 1B shows a conventional structure for the SSE 4 that includes asilicon substrate 12, an N-type gallium nitride (“GaN”) material 14, anindium gallium nitride (“InGaN”) material 16 and/or GaN multiple quantumwells, and a P-type GaN material 18 on one another in series. The SSE 4shown in FIG. 1B can be a lateral-type device that includes a firstcontact 20 on the P-type GaN material 18 and a second contact 22 on theN-type GaN material 14 spaced laterally apart from the first contact 20.

One challenge associated with conventional SSLs (e.g., the SSL 10 shownin FIG. 1A) is that SSL packages generally only emit light from a singleplane. For example, a conventional SSL can include a plurality of SSEsarranged in an array on one surface of a carrier substrate. Thecombination of conventional SSLs to multiple planes of a package cancomplicate manufacture and increase the vertical and lateral size of thepackage. However, devices having multi-plane light emission aredesirable for many applications (e.g., light posts).

Another challenge associated with conventional SSLs is that some of thecomponents are sensitive to heat. Although SSLs produce less heat thanconventional lighting devices, the heat generated by the SSEs can causesuch heat sensitive components to deteriorate and fail over time. Forexample, the phosphor and the junctions in the light producing materialsdeteriorate at a faster rate at higher temperatures than at lowertemperatures. The deterioration of the phosphor causes the light tochange color over time, and the deterioration of the junctions reducesthe light output at a given current (i.e., reduces the efficiency) andthe life span of the device. Adding SSEs to a SSL device increases theheat of the device and thus accelerates the deterioration of the heatsensitive components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a cross-sectional view of a conventional SSL in accordancewith the prior art.

FIG. 1B is a cross-sectional view of an SSE in accordance with the priorart.

FIG. 2 is a partially schematic cross-sectional view of a back-to-backSSL in accordance with several embodiments of the new technology.

FIG. 3 is a partially schematic cross-sectional view of a back-to-backSSL in accordance with several other embodiments of the new technology.

FIG. 4 is a partially schematic cross-sectional view of a back-to-backSSL in accordance with several further embodiments of the newtechnology.

FIG. 5 is a partially schematic cross-sectional view of a back-to-backSSL in accordance with yet further embodiments of the new technology.

FIG. 6 is a partially schematic cross-sectional view of a rotatableback-to-back SSL in accordance with still further embodiments of the newtechnology.

DETAILED DESCRIPTION

Specific details of several embodiments of solid state lights (“SSLs”)and associated methods of manufacturing SSLs are described below. Theterm “SSL” generally refers to “solid state light” and/or “solid statelighting device” according to the context in which it is used. The term“SSE” generally refers to solid state components that convert electricalenergy into electromagnetic radiation in the visible, ultraviolet,infrared and/or other spectra. SSEs include semiconductor light-emittingdiodes (“LEDs”), polymer light-emitting diodes (“PLEDs”), organiclight-emitting diodes (“OLEDs”), or other types of solid state devicesthat convert electrical energy into electromagnetic radiation in adesired spectrum. The term “phosphor” generally refers to a materialthat can continue emitting light after exposure to energy (e.g.,electrons and/or photons). Additionally, packaged SSLs and methods ofmanufacturing SSL assemblies are specifically described below to providean enabling disclosure, but the package and methods can be applied toother SSLs as well. A person skilled in the relevant art will understandthat the new technology may have additional embodiments and that the newtechnology may be practiced without several of the details of theembodiments described below with reference to FIGS. 2-6.

FIG. 2 illustrates a back-to-back SSL 200 configured in accordance withseveral embodiments of the new technology. The SSL 200 can include acarrier substrate 202 having a plurality of through substrateinterconnects (TSIs) 208, e.g., two TSIs (identified individually as afirst TSI 208 a and a second TSI 208 b). The SSL 200 can further includea plurality of SSEs 210, e.g., two SSEs (identified individually as afirst SSE 210 a and a second SSE 210 b) electrically coupled to the TSIs208. In the illustrated embodiment, the carrier substrate 202 includes afirst surface 204 and a second surface 206 opposite the first surface204 with the TSIs 208 extending from the first surface 204 to the secondsurface 206. In the SSL 200 illustrated in FIG. 2, the SSEs 210 eachhave a front side 212 and a back side 214 opposite the front side 212.The back side 214 of the first SSE 210 a can be proximate (e.g., theclosest surface of the SSE 210 a) to the first surface 204 of thecarrier substrate 202, and the back side 214 of the second SSE 210 b canbe proximate to the second surface 206 of the carrier substrate 202. Thefirst and second SSEs 210 a-b can be electrically coupled to both thefirst TSI 208 a and the second TSI 208 b. In further embodiments, theSSL 200 can include additional SSEs 210 proximate to the first surface204 and/or the second surface 206 of the carrier substrate 202 withcorresponding TSIs 208 electrically coupled to the SSEs 210.

The individual SSEs 210 can include a first semiconductor material 218having a first contact 226, an active region 220, and a secondsemiconductor material 222 having a second contact 228. The firstsemiconductor material 218 can be an N-type semiconductor material, suchas N-type gallium nitride (“N-GaN”), and the second semiconductormaterial 222 can be a P-type semiconductor material, such as P-typegallium nitride (“P-GaN”). The active region 220 can be indium galliumnitride (“InGaN”). The first semiconductor material 218, active region220, and second semiconductor material 222 can be deposited sequentiallyusing chemical vapor deposition (“CVD”), physical vapor deposition(“PVD”), atomic layer deposition (“ALD”), plating, or other techniquesknown in the semiconductor fabrication arts. In the embodimentillustrated in FIG. 2, the first semiconductor material 218 is at thefront side 212 of each SSE 210, and the second semiconductor material222 is at the back side 214. In other embodiments, the semiconductormaterials can be reversed, such that the first semiconductor material218 is at the back side 214 and the second semiconductor material 222 isat the front side 212.

The SSEs 210 can be configured to emit light in the visible spectrum(e.g., from about 390 nm to about 750 nm), in the infrared spectrum(e.g., from about 1050 nm to about 1550 nm), and/or in other suitablespectra. In some embodiments, the SSEs 210 can emit light havingapproximately equivalent wavelengths such that the SSL 200 emits auniform color of light. In other embodiments, the first SSE 210 a canemit light having a first wavelength and the second SSE 210 b can emitlight having a second wavelength different from the first wavelengthsuch that the SSL 200 can emit more than one color of light and/or thewavelengths can be combined to create a different color of light.

In some embodiments, the SSEs 210 can optionally include a reflectivematerial 242 attached with a transparent electrically conductivematerial (not shown) to the back side 214 of one or more SSEs 210. Thereflective material 242 can be silver (Ag), gold (Au), copper (Cu),aluminum (Al), or any other suitable material that reflects lightemitted from the active region 220 so as to redirect the light backthrough second semiconductor material 222, the active region 220, andthe first semiconductor material 218. The reflective material 242 canhave a high thermal conductivity. The reflective material 242 can alsobe selected based on the color of light it reflects. For example, silvergenerally does not alter the color of the reflected light. Gold, copperor other reflective, colored materials can affect the color of the lightand can accordingly be selected to produce a desired color for the lightemitted by the SSL 200. The transparent conductive material can beindium tin oxide (ITO) or any other suitable material that istransparent, electrically conductive, and adheres the reflectivematerial to the second semiconductor material 222. The transparentconductive material and reflective material 242 can be deposited usingCVD, PVD, ALD, plating, or other techniques known in the semiconductorfabrication arts.

To obtain certain colors of light from the SSL 200, a converter material216 (e.g., phosphor, shown in dashed lines) can be placed over the SSL200 such that light from the SSEs 210 irradiates energized particles(e.g., electrons and/or photons) in the converter material 216. Theirradiated converter material 216 then emits light of a certain quality(e.g., color, warmth, intensity, etc.). Alternatively, the convertermaterial 216 can be spaced apart from the SSL 200 in any other locationthat is irradiated by the SSL 200. In one embodiment, the convertermaterial 216 can include a phosphor containing cerium (III)-dopedyttrium aluminum garnet (YAG) at a particular concentration for emittinga range of colors from green to yellow and to red underphotoluminescence. In other embodiments, the converter material 216 caninclude neodymium-doped YAG, neodymium-chromium double-doped YAG,erbium-doped YAG, ytterbium-doped YAG, neodymium-cerium double-dopedYAG, holmium-chromium-thulium triple-doped YAG, thulium-doped YAG,chromium (IV)-doped YAG, dysprosium-doped YAG, samarium-doped YAG,terbium-doped YAG, and/or other suitable wavelength conversionmaterials. In additional embodiments, different converter materials 216can be placed over the first SSE 210 a and the second SSE 210 b so theSSL 200 can emit multiple, different qualities of light. In furtherembodiments, the converter material 216 can differ on each surface(e.g., the first surface 204, the second surface 206, etc.) of thecarrier substrate 202, such that the SSL 200 emits differing qualitiesof light from different surfaces. Each surface of the carrier substrate202 can provide a natural barrier for differing converter materials 216,thereby simplifying the placement of different converter materials 216on the SSE 200.

The carrier substrate 202 can comprise an aluminum nitride (ALN)material. Aluminum nitride is an electrically insulating ceramic with ahigh thermal conductivity. Thus, embodiments of SSL 200 including thealuminum nitride carrier substrate 202 can efficiently transfer heatfrom the SSEs 210 without interfering with the electrical properties ofcontacts, TSIs, leads, and/or other electrical features. The coolingeffect of aluminum nitride is especially advantageous for back-to-backSSLs, such as the SSL 200, because the addition of SSEs 210 on multiplesurfaces of the carrier substrate 202 can otherwise impede heat transferfrom the SSL 200, which can degrade heat sensitive components. In otherembodiments, the carrier substrate can comprise another suitabledielectric material (e.g., silicon).

The carrier substrate 202 can further include a plurality of leads 232for providing electrical connections to the SSEs 210. For example, thecarrier substrate 202 illustrated in FIG. 2 includes a first lead 232 acoupled to a negative potential and a second lead 232 b coupled to apositive potential. In further embodiments, the potentials can bereversed such that the first lead 232 a couples to the positivepotential and the second lead 232 b couples to the negative potential.In still further embodiments, the carrier substrate 202 can includeadditional leads 232 to provide an electrical connection for additionalSSEs 210.

The plurality of TSIs 208 extending through the carrier substrate 202can include one or more electrically conductive materials. For example,the conductive material can comprise copper (Cu), aluminum (Al),tungsten (W), and/or other suitable substances or alloys. The TSIs 208can further include a thermally conductive material that transfers heataway from the SSEs 210 to provide cooling for the SSEs 210. The TSIs 208can be any shape and size suitable for electrical and/or thermalconductivity. In some embodiments, the TSIs 208 can be formed byremoving portions of the carrier substrate 202 using etching, laserdrilling, or other suitable techniques known to those skilled in theart. The resultant apertures in the carrier substrate 202 can be atleast partially filled with the electrically conductive material(s)using plating, physical vapor deposition (PVD), chemical vapordeposition (CVD), or other suitable techniques known to those skilled inthe art. If necessary, a portion of the carrier substrate 202 can beremoved (e.g., by backgrinding) to form the TSIs 208. In otherembodiments, the carrier substrate 202 can include pre-formed aperturesthat can be at least partially filled with the electrically conductivematerial(s). The TSIs 208 can be formed by removing a portion of thecarrier substrate 202 using backgrinding or other techniques known inthe art.

The TSIs 208 can provide an electrical connection between the SSEs 210and the leads 232. In FIG. 2, for example, the first TSI 208 a can becoupled to the first lead 232 a and the second TSI 208 b can be coupledto the second lead 232 b, such that the first TSI 208 a can be anegative terminal and the second TSI 208 b can be a positive terminal.The exposed ends of the TSIs 208 at the first surface 204 of the carriersubstrate 202 can be coupled to the first SSE 210 a, and the exposedends of the TSIs 208 at the second surface 206 of the carrier substrate202 can be coupled to the second SSE 210 b. In the embodimentillustrated in FIG. 2, the second semiconductor material 222 and theactive region 220 of the each SSE 210 expose the first contact 226 onthe first semiconductor material 218. The SSEs 210 having thisconfiguration can include one or more conductive members 230 that couplethe first contacts 226 to the exposed ends of the first TSI 208 a and/orthe second contacts 228 to the exposed ends of the second TSI 208 b. Inthe embodiment illustrated in FIG. 2, the conductive members can besolder balls comprising copper (Cu), aluminum (Al), tungsten (W), and/orother suitable electrically conductive substances or alloys. Inalternative embodiments, the first and second contacts 226 and 228 canbe coupled to the corresponding TSIs 208 using different techniquesknown in the art (e.g., surface mounting, wirebonding, etc.).

In operation, the SSEs 210 convert electrical energy intoelectromagnetic radiation in a desired spectrum causing the first SSE210 a to emit light away from the first surface 204 of the carriersubstrate 202 and the second SSE 210 b to emit light away from thesecond surface 206. Thus, unlike conventional SSLs that emit light froma single plane, SSLs in accordance with the new technology (e.g., theSSL 200) can emit light from a plurality of planes. This can increasethe intensity of illumination and/or create a wide angle of illumination(e.g., 360° of illumination). Additionally, since SSLs in accordancewith the new technology utilize more than one surface of the associatedcarrier substrates, the SSLs can have a smaller footprint and/or a morecompact size in the vertical and lateral directions than conventionalSSLs that must be combined to create somewhat similar features. Thus,SSLs in accordance with the new technology can be particularlyadvantageous where three dimensional illumination is required (e.g.,light posts) and/or where a high intensity of light in a small space(e.g., cell phones) is desired.

In the embodiment illustrated in FIG. 2, the first and second SSEs 210a-b are proximate to the first surface 204 and the second surface 206 ofthe carrier substrate 202 and have an angle of incidence ofapproximately 180°. In alternative embodiments, the SSEs 210 can be onmore than two surfaces of the carrier substrate 202 and/or can have asmaller or larger angle of incidence between the SSEs 210. In oneembodiment, for example, the carrier substrate 202 can be a hexagonalprism and include one or more SSEs 210 on each of its eight surfaces.

FIG. 3 is a partially schematic cross-sectional view of a back-to-backSSL 300 in accordance with several embodiments of the new technology.Several features of the SSL 300 are generally similar to the features ofFIG. 2 and are accordingly not described in detail below. The SSEs 210shown in FIG. 3 include a wirebond 234 between the carrier substrate 202and the SSEs 210. For example, in the illustrated embodiment, the firstcontacts 226 can be on the front surfaces 212 of each corresponding SSE210 and the first TSI 208 a can be laterally spaced apart from the SSEs210, such that each first contact 226 can be electrically coupled to thecorresponding exposed end of the first TSI 208 a with the correspondingwirebond 234. The second contacts 228 can be surface mounted to thecorresponding exposed ends of the second TSI 208 b. In otherembodiments, the first and second contacts 226 and 228 can beelectrically coupled to the TSIs 208 using other suitable methods knownto those skilled in the art. In the configuration illustrated in FIG. 3,only one contact (e.g., the second contact 228) need be aligned with aTSI 208 to form an electrical connection, thereby easing the alignmentrequirements during manufacturing.

FIG. 4 is a partially schematic cross-sectional view of a back-to-backSSL 400 in accordance with several embodiments of the new technology.Several features of the SSL 400 are generally similar to the features ofFIGS. 2-3 and are accordingly not described in detail below. In FIG. 4,the first contacts 226 are buried contacts in the first semiconductormaterials 218 of the first and second SSEs 210. The SSL 400 can includeconnectors 236 extending from each end of the first TSI 208 a to thecorresponding first contact 226 that electrically couple the twocomponents. The connector 236 can comprise copper (Cu), aluminum (Al),gold (Au), tungsten (W), and/or other suitable conductive materials. Theconnector 236 can be at least partially surrounded by a dielectricmaterial 238, such that the connector 236 is electrically isolated fromportions of the SSE 210 other than the first contact 226 (e.g., thesecond semiconductor material 222 and the active material 220). In someembodiments, the connector 236 and the TSI 208 can be integrally formed.Advantageously, the buried contact allows the SSEs 210 to sit flush withthe carrier substrate 202, thereby giving the SSL 400 a more compactsize in the vertical and lateral directions.

FIG. 5 is a partially schematic cross-sectional view of a back-to-backSSL 500 in accordance with several embodiments of the new technology.Several features of the SSL 500 are generally similar to the features ofFIGS. 2-4 and are accordingly not described in detail below. In FIG. 5,the carrier substrate 202 further includes a conductive core 240comprising a highly thermally conductive material, such as aluminum(Al), gold (Au), copper (Cu), and/or another suitable materials. In theillustrated embodiment, the conductive core 240 is electrically isolatedfrom the TSIs 208, the SSEs 210, the leads 232, and/or other electricalfeatures. The conductive core 240 can increase the transfer of heat awayfrom SSEs 210 to provide cooling for the SSL 500. In some embodiments,the SSL 500 can include a carrier substrate comprising an aluminumnitride material and the conductive core 240 to provide exceptionalcooling effects.

FIG. 6 is a partially schematic cross-sectional view of a rotatableback-to-back SSL 600 in accordance with several embodiments of the newtechnology. The SSL 600 can include several features generally similarto any of the above SSLs described in FIGS. 2-5, such as the carriersubstrate 202 and the plurality of SSEs 210. The SSL 600 can furtherinclude a rotation device 650 configured to rotate the SSEs 210 aroundone or more axis, such as the axis Y-Y. In one embodiment, the rotationdevice 650 can spin the SSEs 210 at a first speed such that the SSL 600emulates a blinking light. For example, each SSE 210 can emit a streamof light and the rotation device 650 can spin the SSL 600 at a firstspeed, such that the human eye can perceive the intermittent breaks inthe light as the SSL 600 rotates to expose surfaces of the carriersubstrate 202 without light emitted by the SSEs 210. In anotherembodiment, the rotation device 650 can spin the SSL 600 at a secondspeed higher than the first speed, such that the SSL 600 emulates agenerally constant stream of light at a point spaced apart from the SSL600. For example, a generally constant stream of light means therotation device 650 can spin the SSL 600 at a speed that prevents thehuman eye from perceiving surfaces of the carrier substrate 202 withoutthe SSEs 210. In some embodiments, the first SSE 210 a can emit a firstcolor of light and the second SSE 210 b can emit a second color of lightdifferent than the first color, such that the first and second colors oflight can combine to emit a third color of light when the rotationdevice 650 spins the SSL 600 at the second speed. In furtherembodiments, the SSEs can emit more than two colors of light. In stillfurther embodiments, the SSL 600 can include additional SSEs on one ormore surfaces of the carrier substrate, and/or the rotation device 650can spin the SSL 600 at varying speeds around one or more axis.

From the foregoing, it will be appreciated that specific embodiments ofthe present technology have been described herein for purposes ofillustration, but that various modifications may be made withoutdeviating from the technology. For example, the embodiments illustratedin FIGS. 2-6 include through substrate interconnects having a straighttrajectory. However, other embodiments of the new technology can includethrough substrate interconnects having angled, curved, and/or othertrajectories that can electrically connect SSEs on different surfaces ofcarrier substrates. Certain aspects of the new technology described inthe context of particular embodiments may be combined or eliminated inother embodiments. For example, the SSL of FIG. 6 can include any of theforegoing SSL arrangements. Additionally, an SSL in accordance with thetechnology can include a combination of SSEs having any one of theforgoing configurations. For example, an SSL can include a SSE asillustrated in FIG. 2 and another SSE as illustrated in FIG. 4. Further,while advantages associated with certain embodiments of the newtechnology have been described in the context of those embodiments,other embodiments may also exhibit such advantages, and not allembodiments need necessarily exhibit such advantages to fall within thescope of the technology. Accordingly, the disclosure and associatedtechnology can encompass other embodiments not expressly shown ordescribed herein.

We claim:
 1. A solid state light (SSL), comprising: a first throughsubstrate interconnect (TSI) extending from a first surface of a carriersubstrate to a second surface of the carrier substrate different fromthe first surface; a second TSI extending from the first surface of thecarrier substrate to the second surface of the carrier substrate; afirst solid state emitter (SSE) mounted to the first surface of thecarrier substrate; and a second SSE mounted to the second surface of thecarrier substrate; wherein a first reflective material is attached tothe first SSE with a first transparent electrically conductive material,and wherein the first reflective material is disposed between the firstSSE and the carrier substrate and in direct contact with a firstelectrically insulative material at the first surface carrier substrate,wherein a second reflective material is attached to the second SSE witha second transparent electrically conductive material, and wherein thesecond reflective material is disposed between the second SSE and thecarrier substrate and in direct contact with a second electricallyinsulative material at the second surface of the carrier substrate,wherein the first TSI is electrically coupled to the first and secondSSEs, wherein the second TSI is electrically coupled to the first andsecond SSEs, and wherein the first and second SSEs directly overlap thefirst and second TSIs.
 2. The SSL of claim 1, wherein: the first surfaceof the carrier substrate is opposite the second surface; the first SSEcomprises a first semiconductor material at a first side of the firstSSE, a second semiconductor material at a second side of the first SSLopposite the first side, wherein the second side faces the first surfaceof the carrier substrate, wherein the first semiconductor materialincludes a first contact and the second semiconductor material includesa second contact; the second SSE comprises a first semiconductormaterial at a first side of the second SSE, a second semiconductormaterial at a second side of the second SSL opposite from the firstside, wherein the second side faces the second surface of the carriersubstrate, and wherein the first semiconductor material includes a firstcontact and the second semiconductor material includes a second contact,the first contacts of the first and second SSEs are electrically coupledto the first TSI, and the second contacts of the first and second SSEsare electrically coupled to the second TSI.
 3. The SSL of claim 2,wherein: the first contact of the first SSE is exposed; and the firstcontact is electrically coupled to the first TSI with a conductivemember.
 4. The SSL of claim 2, wherein the first contacts of the firstand second SSEs are buried contacts, further comprising: a firstaperture in the first SSE, wherein the first aperture extends from thesecond side of the first SSE to the first contact buried in the firstSSE; a second aperture in the second SSE, wherein the second apertureextends from the second side of the second SSE to the first contactburied in the second SSE; a first electrical connector extending fromthe first TSI through the first aperture to the first contact buried inthe first SSE; a second electrical connector extending from the firstTSI through the second aperture to the first contact buried in thesecond SSE; and a dielectric material in the first and second apertures,wherein the dielectric material is configured to electrically isolatethe first and second electrical connectors from at least the secondsemiconductor material.
 5. The SSL of claim 1 wherein the carriersubstrate comprises aluminum nitride.
 6. The SSL of claim 1 wherein thecarrier substrate comprises a conductive core electrically isolated fromthe first and second TSIs and the first and second SSEs.
 7. The SSL ofclaim 1, further comprising: a rotation device coupled to the first andsecond SSEs to rotate the first and second SSEs around at least oneaxis.
 8. The SSL of claim 7 wherein the rotation device rotates the SSLat a speed at least sufficient to emulate a generally constant stream oflight from the SSL.
 9. The SSL of claim 8 wherein the rotation devicerotates the SSL at a speed that produces intermittent flashes of lightfrom the SSL.
 10. The SSL of claim 1 wherein the first SSE is one of aplurality of first SSEs, the second SSE is one of a plurality of secondSSEs, and the first and second TSIs are one of a plurality of first andsecond TSIs corresponding to the plurality of first and second SSEs. 11.The SSL of claim 1 wherein the first SSE emits a first color of lightand the second SSE emits a second color of light different from thefirst color of light.
 12. The SSL of claim 1, further comprising: afirst converter material at least partially over the first SSE; and asecond converter material different from the first converter material atleast partially over the second SSE.
 13. The SSL of claim 1, furthercomprising: at least one additional SSE mounted to a third surface ofthe carrier substrate, wherein the first TSI is electrically coupled tothe additional SSE; and the second TSI is electrically coupled to theadditional SSE.